Again, that remarkable island Madagascar is the home of very singular and special insectivorous beasts of the genera Centetes, Ericulus, and Echinops; while the only other member of the group to which they belong is Solenodon, which is a resident in the West Indian Islands, Cuba and Hayti. The connexion, however, between the West Indies and Madagascar must surely have been at a time when the great lemurine group was absent; for it is difficult to understand the spread of such a form as Solenodon, and at the same time the non-extension of the active lemurs, or their utter extirpation, in such a congenial locality as the West Indian Archipelago. The close connexion of South America and Australia is demonstrated (on the Darwinian theory), not only from the marsupial fauna of both, but also from the frogs and toads which respectively inhabit those regions. A truly remarkable similarity and parallelism exist, however, between certain of the same animals inhabiting South Western America and Europe. Thus Dr.{149} Guenther has described[156] a frog from Chile by the name of cacotus, which singularly resembles the European bombinator. [Illustration: SOLENODON.] Again of the salmons, two genera from South America, New Zealand, and Australia, are analogous to European salmons. In addition to this may be mentioned a quotation from Professor Dana, given by Mr. Darwin,[157] to the effect that "it is certainly a wonderful fact that New Zealand should have a closer resemblance in its crustacea to Great Britain, its antipode, than to any other part of the world:" and Mr. Darwin adds "Sir J. Richardson also speaks of the reappearance on the shores of New Zealand, Tasmania, &c. of northern forms of fish. Dr. Hooker informs me that twenty-five species of algae are common to New Zealand and to {150} Europe, but have not been found in the intermediate tropical seas." Many more examples of the kind could easily be brought, but these must suffice. As to the last-mentioned cases Mr. Darwin explains them by the influence of the glacial epoch, which he would extend actually across the equator, and thus account, amongst other things, for the appearance in Chile of frogs having close genetic relations with European forms. But it is difficult to understand the persistence and preservation of such exceptional forms with the extirpation of all the others which probably accompanied them, if so great a migration of northern kinds had been occasioned by the glacial epoch.